Global config for Hearth clients

codegen/smithy-ruby-codegen-test-utils/src/main/java/software/amazon/smithy/ruby/codegen/integrations/WhiteLabelTestIntegration.java

@@ -42,7 +42,7 @@ public boolean includeFor(ServiceShape service, Model model) {
     }
 
     @Override
-    public List<RubyRuntimePlugin> getRuntimePlugins(GenerationContext context) {
+    public List<RubyRuntimePlugin> getAdditionalRuntimePlugins(GenerationContext context) {
         return List.of(RubyRuntimePlugin.builder()
                 .rubySource("plugins/test_plugin.rb")
                 .pluginClass("Plugins::TestPlugin")

codegen/smithy-ruby-codegen/src/main/java/software/amazon/smithy/ruby/codegen/DirectedRubyCodegen.java

@@ -42,6 +42,7 @@
 import software.amazon.smithy.ruby.codegen.generators.ConfigGenerator;
 import software.amazon.smithy.ruby.codegen.generators.EndpointGenerator;
 import software.amazon.smithy.ruby.codegen.generators.GemspecGenerator;
+import software.amazon.smithy.ruby.codegen.generators.GlobalConfigPluginGenerator;
 import software.amazon.smithy.ruby.codegen.generators.HttpProtocolTestGenerator;
 import software.amazon.smithy.ruby.codegen.generators.MiddlewareGenerator;
 import software.amazon.smithy.ruby.codegen.generators.ModuleGenerator;
@@ -166,6 +167,9 @@ public void generateService(GenerateServiceDirective<GenerationContext, RubySett
         configGenerator.render();
         configGenerator.renderRbs();
 
+        GlobalConfigPluginGenerator globalConfigPluginGenerator = new GlobalConfigPluginGenerator(directive);
+        globalConfigPluginGenerator.render();
+
         MiddlewareGenerator middlewareGenerator = new MiddlewareGenerator(directive, middlewareBuilder);
         middlewareGenerator.render();
 

codegen/smithy-ruby-codegen/src/main/java/software/amazon/smithy/ruby/codegen/GenerationContext.java

@@ -20,6 +20,7 @@
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
@@ -298,13 +299,17 @@ public Set<RubyDependency> getRubyDependencies() {
      * @return Set of all RubyRuntimePlugins from all integrations
      */
     public Set<RubyRuntimePlugin> getRuntimePlugins() {
-        return integrations.stream()
-                .map((i) -> i.getRuntimePlugins(this))
-                .flatMap(List::stream)
-                .collect(Collectors.toUnmodifiableSet());
+        Set<RubyRuntimePlugin> runtimePlugins = new LinkedHashSet<>();
+        runtimePlugins.add(RubyRuntimePlugin.builder()
+                .pluginClass("Plugins::GlobalConfig")
+                .writeAdditionalFiles(context -> Collections.singletonList("plugins/global_config.rb"))
+                .build());
+        integrations.forEach((i) -> {
+            runtimePlugins.addAll(i.getAdditionalRuntimePlugins(this));
+        });
+        return Collections.unmodifiableSet(runtimePlugins);
     }
 
-
     /**
      * @return Set of AuthSchemes that apply to this service.
      */

codegen/smithy-ruby-codegen/src/main/java/software/amazon/smithy/ruby/codegen/Hearth.java

@@ -22,6 +22,10 @@
  */
 public final class Hearth {
 
+    public static final Symbol HEARTH = Symbol.builder()
+            .name("Hearth")
+            .build();
+
     public static final Symbol CLIENT = Symbol.builder()
             .namespace("Hearth", "::")
             .name("Client")

codegen/smithy-ruby-codegen/src/main/java/software/amazon/smithy/ruby/codegen/RubyCodeWriter.java

@@ -129,7 +129,7 @@ public RubyCodeWriter preamble() {
     }
 
     /**
-     * Require statments for symbols/dependenices used
+     * Require statements for symbols/dependencies used
      * will be included in the generated code.
      * This should be called for writers that are used to generate full files.
      *

codegen/smithy-ruby-codegen/src/main/java/software/amazon/smithy/ruby/codegen/RubyIntegration.java

@@ -81,7 +81,7 @@ default List<ClientConfig> getAdditionalClientConfig(GenerationContext context)
      * @param context - Generation context to process within
      * @return List of RubyRuntimePlugins
      */
-    default List<RubyRuntimePlugin> getRuntimePlugins(GenerationContext context) {
+    default List<RubyRuntimePlugin> getAdditionalRuntimePlugins(GenerationContext context) {
         return Collections.emptyList();
     }
 

codegen/smithy-ruby-codegen/src/main/java/software/amazon/smithy/ruby/codegen/generators/GlobalConfigPluginGenerator.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package software.amazon.smithy.ruby.codegen.generators;
+
+import java.nio.file.Paths;
+import java.util.logging.Logger;
+import software.amazon.smithy.codegen.core.directed.ContextualDirective;
+import software.amazon.smithy.ruby.codegen.GenerationContext;
+import software.amazon.smithy.ruby.codegen.Hearth;
+import software.amazon.smithy.ruby.codegen.RubyCodeWriter;
+import software.amazon.smithy.ruby.codegen.RubyFormatter;
+import software.amazon.smithy.ruby.codegen.RubySettings;
+import software.amazon.smithy.utils.SmithyInternalApi;
+
+/**
+ * Generate Config class for a Client.
+ */
+@SmithyInternalApi
+public class GlobalConfigPluginGenerator extends RubyGeneratorBase {
+    private static final Logger LOGGER =
+            Logger.getLogger(ConfigGenerator.class.getName());
+
+    public GlobalConfigPluginGenerator(
+            ContextualDirective<GenerationContext, RubySettings> directive) {
+        super(directive);
+    }
+
+    @Override
+    protected String getModule() {
+        return "Plugins";
+    }
+
+    @Override
+    public String rbFile() {
+        return Paths.get(settings.getGemName(), "lib", settings.getGemName(),
+                RubyFormatter.toSnakeCase(getModule()), "global_config.rb").toString();
+    }
+
+    public void render() {
+        write(writer -> {
+            writer
+                    .preamble()
+                    .includeRequires()
+                    .addModule(settings.getModule())
+                    .addModule("Plugins")
+                    .openBlock("class GlobalConfig")
+                    .call(() -> renderCallMethod(writer))
+                    .closeBlock("end")
+                    .closeAllModules();
+        });
+        LOGGER.fine("Wrote config defaults plugin to " + rbFile());
+    }
+
+    private void renderCallMethod(RubyCodeWriter writer) {
+        writer
+                .openBlock("def call(config)")
+                .write("options = config.options")
+                .openBlock("$T.config.each do |key, value|", Hearth.HEARTH)
+                .write("config[key] = value unless options.key?(key)")
+                .closeBlock("end")
+                .closeBlock("end");
+    }
+}

hearth/lib/hearth.rb

@@ -53,6 +53,25 @@
 require_relative 'hearth/waiters/waiter'
 require_relative 'hearth/xml'
 
+# Hearth is a low-level Ruby component library for code generated clients using
+# the Smithy modeling language.
 module Hearth
   VERSION = File.read(File.expand_path('../VERSION', __dir__)).strip
+
+  @config = {}
+
+  class << self
+    # @return [Hash] Returns a hash of default configuration options shared
+    #   by all constructed clients.
+    attr_reader :config
+
+    # @param [Hash] config
+    def config=(config)
+      unless config.is_a?(Hash)
+        raise ArgumentError, 'configuration must be a hash'
+      end
+
+      @config = config
+    end
+  end
 end